This invention relates to a vector calculation apparatus for carrying out vector calculation on a plurality of vectors. It is to be noted throughout the instant specification that each of the vectors is composed of a plurality of vector components or elements. These are in the form of electrical signals for electrical processing, although a specific description will not be made hereinafter.
A recent requirement for an electronic digital computer is to process a vector calculation at a high speed. The vector calculation is, for example, vector addition of calculating a sum of a pair of vectors. During the vector addition, addition of components of the respective vectors must be repeated a great number of times. This is because each of the vectors is usually composed of many components.
Various conventional vector calculation apparatus are used in the electronic digital computer. One conventional vector calculation apparatus includes a two-input vector adder for carrying out addition of two adder input signals. Supplied with the vectors as the adder input signals, the two-input vector adder carries Out the addition to produce an adder output signal representative of the sum of vectors. This vector calculation apparatus requires a relatively long time as will later be described in detail.
A different conventional vector calculation apparatus includes a three-input vector adder and a selecting circuit. The three-input vector adder is for carrying out addition of three adder input signals to produce an adder output signal. The selecting circuit is for selecting, as a selected signal, a selected one of the adder output signal and a predetermined value, such as zero. Supplied with the vectors and the selected signal as the adder input signals, the three-input vector adder carries out the addition to produce the adder output signal. As will later be described in detail, different this other vector calculation apparatus has a disadvantage in that a very long time is necessary to calculate the sum in the case where the vectors are composed of an enormous number of components.